//===- CodeGeneratorBug.cpp - Debug code generation bugs ------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file implements program code generation debugging support.
//
//===----------------------------------------------------------------------===//
#include "BugDriver.h"
-#include "SystemUtils.h"
#include "ListReducer.h"
-#include "llvm/Pass.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/GlobalValue.h"
+#include "llvm/iMemory.h"
+#include "llvm/iTerminators.h"
+#include "llvm/iOther.h"
#include "llvm/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Analysis/Verifier.h"
+#include "llvm/Support/Mangler.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/Linker.h"
#include "Support/CommandLine.h"
-#include "Support/Statistic.h"
+#include "Support/Debug.h"
#include "Support/StringExtras.h"
+#include "Support/FileUtilities.h"
#include <algorithm>
#include <set>
-// Passed as a command-line argument to Bugpoint
-extern cl::opt<std::string> Output;
+extern cl::list<std::string> InputArgv;
class ReduceMisCodegenFunctions : public ListReducer<Function*> {
BugDriver &BD;
return NoFailure;
}
- bool TestFuncs(const std::vector<Function*> &CodegenTest);
-
- void DisambiguateGlobalSymbols(Module *M);
+ bool TestFuncs(const std::vector<Function*> &CodegenTest,
+ bool KeepFiles = false);
};
-bool ReduceMisCodegenFunctions::TestFuncs(const std::vector<Function*> &Funcs)
-{
+bool ReduceMisCodegenFunctions::TestFuncs(const std::vector<Function*> &Funcs,
+ bool KeepFiles) {
+ std::cout << "Testing functions: ";
+ BD.PrintFunctionList(Funcs);
+ std::cout << "\t";
+
// Clone the module for the two halves of the program we want.
Module *SafeModule = CloneModule(BD.Program);
for (Module::giterator I=SafeModule->gbegin(),E = SafeModule->gend();I!=E;++I)
I->setLinkage(GlobalValue::ExternalLinkage);
- DisambiguateGlobalSymbols(SafeModule);
Module *TestModule = CloneModule(SafeModule);
// Make sure global initializers exist only in the safe module (CBE->.so)
for (Module::giterator I=TestModule->gbegin(),E = TestModule->gend();I!=E;++I)
I->setInitializer(0); // Delete the initializer to make it external
- // Remove the Test functions from the Safe module, and
- // all of the global variables.
+ // Remove the Test functions from the Safe module
for (unsigned i = 0, e = Funcs.size(); i != e; ++i) {
Function *TNOF = SafeModule->getFunction(Funcs[i]->getName(),
Funcs[i]->getFunctionType());
+ DEBUG(std::cerr << "Removing function " << Funcs[i]->getName() << "\n");
assert(TNOF && "Function doesn't exist in module!");
DeleteFunctionBody(TNOF); // Function is now external in this module!
}
+ // Remove the Safe functions from the Test module
+ for (Module::iterator I=TestModule->begin(),E=TestModule->end(); I!=E; ++I) {
+ bool funcFound = false;
+ for (std::vector<Function*>::const_iterator F=Funcs.begin(),Fe=Funcs.end();
+ F != Fe; ++F)
+ if (I->getName() == (*F)->getName()) funcFound = true;
+
+ if (!funcFound && !(BD.isExecutingJIT() && I->getName() == "main"))
+ DeleteFunctionBody(I);
+ }
+
+ // This is only applicable if we are debugging the JIT:
+ // Find all external functions in the Safe modules that are actually used
+ // (called or taken address of), and make them call the JIT wrapper instead
+ if (BD.isExecutingJIT()) {
+ // Must delete `main' from Safe module if it has it
+ Function *safeMain = SafeModule->getNamedFunction("main");
+ assert(safeMain && "`main' function not found in safe module!");
+ DeleteFunctionBody(safeMain);
+
+ // Add an external function "getPointerToNamedFunction" that JIT provides
+ // Prototype: void *getPointerToNamedFunction(const char* Name)
+ std::vector<const Type*> Params;
+ Params.push_back(PointerType::get(Type::SByteTy)); // std::string&
+ FunctionType *resolverTy = FunctionType::get(PointerType::get(Type::VoidTy),
+ Params, false /* isVarArg */);
+ Function *resolverFunc = new Function(resolverTy,
+ GlobalValue::ExternalLinkage,
+ "getPointerToNamedFunction",
+ SafeModule);
+
+ // Use the function we just added to get addresses of functions we need
+ // Iterate over the global declarations in the Safe module
+ for (Module::iterator F=SafeModule->begin(),E=SafeModule->end(); F!=E; ++F){
+ if (F->isExternal() && !F->use_empty() && &*F != resolverFunc &&
+ F->getIntrinsicID() == 0 /* ignore intrinsics */ &&
+ // Don't forward functions which are external in the test module too.
+ !TestModule->getNamedFunction(F->getName())->isExternal()) {
+ // If it has a non-zero use list,
+ // 1. Add a string constant with its name to the global file
+ // The correct type is `const [ NUM x sbyte ]' where NUM is length of
+ // function name + 1
+ const std::string &Name = F->getName();
+ GlobalVariable *funcName =
+ new GlobalVariable(ArrayType::get(Type::SByteTy, Name.length()+1),
+ true /* isConstant */,
+ GlobalValue::InternalLinkage,
+ ConstantArray::get(Name),
+ Name + "_name",
+ SafeModule);
+
+ // 2. Use `GetElementPtr *funcName, 0, 0' to convert the string to an
+ // sbyte* so it matches the signature of the resolver function.
+ std::vector<Constant*> GEPargs(2, Constant::getNullValue(Type::LongTy));
+
+ // 3. Replace all uses of `func' with calls to resolver by:
+ // (a) Iterating through the list of uses of this function
+ // (b) Insert a cast instruction in front of each use
+ // (c) Replace use of old call with new call
+
+ // GetElementPtr *funcName, ulong 0, ulong 0
+ Value *GEP =
+ ConstantExpr::getGetElementPtr(ConstantPointerRef::get(funcName),
+ GEPargs);
+ std::vector<Value*> ResolverArgs;
+ ResolverArgs.push_back(GEP);
+
+ // Insert code at the beginning of the function
+ while (!F->use_empty())
+ if (Instruction *Inst = dyn_cast<Instruction>(F->use_back())) {
+ // call resolver(GetElementPtr...)
+ CallInst *resolve = new CallInst(resolverFunc, ResolverArgs,
+ "resolver", Inst);
+ // cast the result from the resolver to correctly-typed function
+ CastInst *castResolver =
+ new CastInst(resolve, PointerType::get(F->getFunctionType()),
+ "resolverCast", Inst);
+ // actually use the resolved function
+ Inst->replaceUsesOfWith(F, castResolver);
+ } else {
+ // FIXME: need to take care of cases where a function is used that
+ // is not an instruction, e.g. global variable initializer...
+ std::cerr << "Non-instruction is using an external function!\n";
+ abort();
+ }
+ }
+ }
+ }
+
+ if (verifyModule(*SafeModule) || verifyModule(*TestModule)) {
+ std::cerr << "Bugpoint has a bug, an corrupted a module!!\n";
+ abort();
+ }
+
+ DEBUG(std::cerr << "Safe module:\n";
+ typedef Module::iterator MI;
+ typedef Module::giterator MGI;
+
+ for (MI I = SafeModule->begin(), E = SafeModule->end(); I != E; ++I)
+ if (!I->isExternal()) std::cerr << "\t" << I->getName() << "\n";
+ for (MGI I = SafeModule->gbegin(), E = SafeModule->gend(); I!=E; ++I)
+ if (!I->isExternal()) std::cerr << "\t" << I->getName() << "\n";
+
+ std::cerr << "Test module:\n";
+ for (MI I = TestModule->begin(), E = TestModule->end(); I != E; ++I)
+ if (!I->isExternal()) std::cerr << "\t" << I->getName() << "\n";
+ for (MGI I=TestModule->gbegin(),E = TestModule->gend(); I!= E; ++I)
+ if (!I->isExternal()) std::cerr << "\t" << I->getName() << "\n";
+ );
+
// Write out the bytecode to be sent to CBE
- std::string SafeModuleBC = "bugpoint.safe.bc";
+ std::string SafeModuleBC = getUniqueFilename("bugpoint.safe.bc");
+
if (BD.writeProgramToFile(SafeModuleBC, SafeModule)) {
std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting.";
exit(1);
}
- // Make a shared library
- std::string SharedObject;
- BD.compileSharedObject(SafeModuleBC, SharedObject);
-
// Remove all functions from the Test module EXCEPT for the ones specified in
// Funcs. We know which ones these are because they are non-external in
// ToOptimize, but external in ToNotOptimize.
DeleteFunctionBody(I);
}
- std::string TestModuleBC = "bugpoint.test.bc";
+ std::string TestModuleBC = getUniqueFilename("bugpoint.test.bc");
+ if (verifyModule(*TestModule)) {
+ std::cerr << "Bytecode file corrupted!\n";
+ exit(1);
+ }
+
+ // Clean up the modules, removing extra cruft that we don't need anymore...
+ SafeModule = BD.performFinalCleanups(SafeModule);
+ TestModule = BD.performFinalCleanups(TestModule);
+
if (BD.writeProgramToFile(TestModuleBC, TestModule)) {
std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting.";
exit(1);
}
+ // Make a shared library
+ std::string SharedObject = BD.compileSharedObject(SafeModuleBC);
+
+ delete SafeModule;
+ delete TestModule;
+
// Run the code generator on the `Test' code, loading the shared library.
// The function returns whether or not the new output differs from reference.
- return BD.diffProgram(TestModuleBC, SharedObject, false);
+ int Result = BD.diffProgram(TestModuleBC, SharedObject, false);
+
+ if (Result)
+ std::cerr << ": still failing!\n";
+ else
+ std::cerr << ": didn't fail.\n";
+
+ if (KeepFiles) {
+ std::cout << "You can reproduce the problem with the command line: \n";
+ if (BD.isExecutingJIT()) {
+ std::cout << " lli -load " << SharedObject << " " << TestModuleBC;
+ } else {
+ std::cout << " llc " << TestModuleBC << " -o " << TestModuleBC << ".s\n";
+ std::cout << " gcc " << SharedObject << " " << TestModuleBC
+ << ".s -o " << TestModuleBC << ".exe -Wl,-R.\n";
+ std::cout << " " << TestModuleBC << ".exe";
+ }
+ for (unsigned i=0, e = InputArgv.size(); i != e; ++i)
+ std::cout << " " << InputArgv[i];
+ std::cout << "\n";
+ std::cout << "The shared object was created with:\n llvm-dis -c "
+ << SafeModuleBC << " -o temporary.c\n"
+ << " gcc -xc temporary.c -O2 -o " << SharedObject
+#if defined(sparc) || defined(__sparc__) || defined(__sparcv9)
+ << " -G" // Compile a shared library, `-G' for Sparc
+#else
+ << " -shared" // `-shared' for Linux/X86, maybe others
+#endif
+ << " -fno-strict-aliasing\n";
+ } else {
+ removeFile(TestModuleBC);
+ removeFile(SafeModuleBC);
+ removeFile(SharedObject);
+ }
+ return Result;
}
namespace {
- struct Disambiguator /*: public unary_function<GlobalValue&, void>*/ {
- std::set<std::string> SymbolNames;
- std::set<Value*> Symbols;
+ struct Disambiguator {
+ std::set<std::string> SymbolNames;
+ std::set<GlobalValue*> Symbols;
uint64_t uniqueCounter;
bool externalOnly;
-
+ public:
Disambiguator() : uniqueCounter(0), externalOnly(true) {}
void setExternalOnly(bool value) { externalOnly = value; }
- void operator() (GlobalValue &V) {
+ void add(GlobalValue &V) {
+ // If we're only processing externals and this isn't external, bail
if (externalOnly && !V.isExternal()) return;
+ // If we're already processed this symbol, don't add it again
+ if (Symbols.count(&V) != 0) return;
+ // Ignore intrinsic functions
+ if (Function *F = dyn_cast<Function>(&V))
+ if (F->getIntrinsicID() != 0)
+ return;
+
+ std::string SymName = V.getName();
- if (SymbolNames.count(V.getName()) == 0) {
- DEBUG(std::cerr << "Disambiguator: adding " << V.getName()
+ // Use the Mangler facility to make symbol names that will be valid in
+ // shared objects.
+ SymName = Mangler::makeNameProper(SymName);
+ V.setName(SymName);
+
+ if (SymbolNames.count(SymName) == 0) {
+ DEBUG(std::cerr << "Disambiguator: adding " << SymName
<< ", no conflicts.\n");
- Symbols.insert(&V);
- SymbolNames.insert(V.getName());
+ SymbolNames.insert(SymName);
} else {
// Mangle name before adding
std::string newName;
do {
- newName = V.getName() + "_" + utostr(uniqueCounter);
+ newName = SymName + "_" + utostr(uniqueCounter);
if (SymbolNames.count(newName) == 0) break;
else ++uniqueCounter;
} while (1);
//while (SymbolNames.count(V->getName()+utostr(uniqueCounter++))==0);
- DEBUG(std::cerr << "Disambiguator: conflict: " << V.getName()
+ DEBUG(std::cerr << "Disambiguator: conflict: " << SymName
<< ", adding: " << newName << "\n");
V.setName(newName);
SymbolNames.insert(newName);
- Symbols.insert(&V);
}
+ Symbols.insert(&V);
}
};
}
-void ReduceMisCodegenFunctions::DisambiguateGlobalSymbols(Module *M) {
+void DisambiguateGlobalSymbols(Module *M) {
// First, try not to cause collisions by minimizing chances of renaming an
// already-external symbol, so take in external globals and functions as-is.
- Disambiguator D = std::for_each(M->gbegin(), M->gend(), Disambiguator());
- std::for_each(M->begin(), M->end(), D);
+ Disambiguator D;
+ DEBUG(std::cerr << "Disambiguating globals (external-only)\n");
+ for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I) D.add(*I);
+ DEBUG(std::cerr << "Disambiguating functions (external-only)\n");
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) D.add(*I);
// Now just rename functions and globals as necessary, keeping what's already
// in the set unique.
D.setExternalOnly(false);
- std::for_each(M->gbegin(), M->gend(), D);
- std::for_each(M->begin(), M->end(), D);
+ DEBUG(std::cerr << "Disambiguating globals\n");
+ for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I) D.add(*I);
+ DEBUG(std::cerr << "Disambiguating globals\n");
+ for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) D.add(*I);
}
if (!I->isExternal())
MisCodegenFunctions.push_back(I);
+ // If we are executing the JIT, we *must* keep the function `main' in the
+ // module that is passed in, and not the shared library. However, we still
+ // want to be able to debug the `main' function alone. Thus, we create a new
+ // function `main' which just calls the old one.
+ if (isExecutingJIT()) {
+ // Get the `main' function
+ Function *oldMain = Program->getNamedFunction("main");
+ assert(oldMain && "`main' function not found in program!");
+ // Rename it
+ oldMain->setName("llvm_old_main");
+ // Create a NEW `main' function with same type
+ Function *newMain = new Function(oldMain->getFunctionType(),
+ GlobalValue::ExternalLinkage,
+ "main", Program);
+ // Call the old main function and return its result
+ BasicBlock *BB = new BasicBlock("entry", newMain);
+ std::vector<Value*> args;
+ for (Function::aiterator I = newMain->abegin(), E = newMain->aend(),
+ OI = oldMain->abegin(); I != E; ++I, ++OI) {
+ I->setName(OI->getName()); // Copy argument names from oldMain
+ args.push_back(I);
+ }
+ CallInst *call = new CallInst(oldMain, args);
+ BB->getInstList().push_back(call);
+
+ // if the type of old function wasn't void, return value of call
+ ReturnInst *ret;
+ if (oldMain->getReturnType() != Type::VoidTy) {
+ ret = new ReturnInst(call);
+ } else {
+ ret = new ReturnInst();
+ }
+
+ // Add the return instruction to the BasicBlock
+ BB->getInstList().push_back(ret);
+ }
+
+ DisambiguateGlobalSymbols(Program);
+
// Do the reduction...
- ReduceMisCodegenFunctions(*this).reduceList(MisCodegenFunctions);
+ if (!ReduceMisCodegenFunctions(*this).reduceList(MisCodegenFunctions)) {
+ std::cerr << "*** Execution matches reference output! "
+ << "bugpoint can't help you with your problem!\n";
+ return false;
+ }
std::cout << "\n*** The following functions are being miscompiled: ";
PrintFunctionList(MisCodegenFunctions);
std::cout << "\n";
// Output a bunch of bytecode files for the user...
- ReduceMisCodegenFunctions(*this).TestFuncs(MisCodegenFunctions);
+ ReduceMisCodegenFunctions(*this).TestFuncs(MisCodegenFunctions, true);
return false;
}
-